Article embodying thin foils or sheets



March 3,1942.

F. KRONER ARTICLE EMBODYING THIN FOILS OR SHEETS Filed Oct. 21, 1937 //1 yew/0r obldci K "7 t 42%,

Patented Mar. 3, 1942 ARTICLE EMBODYING THIN FOILS OR SHEETS Friedrich Kroner, Berlin-Charlottenburg, Germany, assignor to Transart Aktiebolag, Gotebox-g, Sweden Application October 21, 1937, Serial No. 170,225 In Germany October 21, 1936 3 Claims.

My invention relates to a method of treating thin foils and sheets, more particularly foils or sheets of transparent cellulose material, and to articles embodying foils or sheets of this kind.

It is the object of the invention to prevent the thin foils or sheets from adhering to each other or sticking together and to reduce the friction between superposed sheets.

Another object of the invention is to facilitate the separation of such foils or sheets.

Still another object of the invention is to render visible whether or not several thin foils are superposed and to facilitate the turning over of the single sheets individually.

According to this invention, the single sheets which may or may not be assembled in the form of a book or catalogue or booklet, are provided at or near their edges with separating layers.

The invention will be better understood from the following detailed description with reference to the acompanying drawing, showing by way of example and schematically one embodiment of the invention, and in which:

Figure 1 is a plan view of several superposed sheets, forming a book.

Figure 2 is a section on line IIII in Figure 1.

Figures 3 and 4 are partial sections of other forms of separating layers applied to a sheet.

From Figures 1 and 2, it will be seen that three sheets I, 2 and 3 are arranged in superposed position and bound together along their left hand edge by a strip 1, the upper end of which is attached to the cover 5 of the book which is shown broken away. The lower end of the strip is connected to the back 4 of the book, as shown in Fig. 2. Of course, this structure may take any form known in bookbinding or may be left out entirely, since the invention also applies to loose sheets or foils.

The sheet I is provided with a separating element in the form of a frame I, as indicated in Figure 2 and in the lower right hand corner of Figure 1 where the sheets 2 and 3 are shown broken away, as indicated by the edges 2 and 3".

The sheet 2 in turn is provided with a separating element- 2', as shown in Figure 2 and in the lower right hand corner of Figure 1 where the sheet 3 is shown broken away. The element 2 in this case is in the form of single semi-circles but may be of any other shape.

The sheet 3 is provided with separating elements in the form of triangles 3. The separating elements I, 2', 3' may be applied in any suitable manner, as for instance by printing or coating or cementing. These elements may be opaque or transparent and may consist of a lacquer or varnish or other paint, a metal deposit or a strip of paper. The separating elements are made of a material which has low adhesion at its upper surface so as to prevent adhesion and the sticking together of the individual sheets I, 2, 3.

In some instances, it may be useful to make the separating elements of metal or of a paint or other deposit of an electrically conductive nature such as a paint containing metal dust in order to prevent the accumulation of static electricity on the sheets due to frictional electricity tending to increase the mutual attraction and adhesion between the sheets.

If the separating elements are made to have a sharp and distinctly visible edge line, they may be used as gauge marks or register marks to ensure accurate register of the superposed sheets in a printing or bookbinding operation.

According to Figure 3, the separating elements I are arranged on both sides of the sheet while according to Figure 4, the two elements are connected with each other at the outer edge which may be useful in order to form an electric conduit.

While I have herein shown and described certain preferred embodiments of my invention, I wish it to be understood that I do not confine myself to the various details herein set forth by way of illustration, as modifications and variations may be made without departing from the spirit of the invention or exceeding the scope of the appended claims.

Especially, it is not necessary for the separating elements to extend to the real edge or corner of the sheets, but they may be disposed at a certain distance from the edge or corner.

I claim:

1. A package of thin transparent cellulose sheets or foils arranged in superposed relation-- ship and tending, under the influence of a frictional contact, to adhere to each other, and an adhesion-reducing strip of electrically conductive material secured to at least an edge portion of each sheet on at least one side thereof, whereby such an element is provided between consecutive sheets or foils of said package thereby facilitating the separation of said sheets or foils from each other.

2. A package of thin transparent cellulose sheets or foils arranged in superposed relationship and tending, under the influence of frictional contact, to adhere to each other, and an adhesion-reducing element of electrically conductive material secured to at least a portion of each sheet on at least one side of said sheet and extending to and along the edge thereof, said elements being identical in configuration and being located at corresponding points on said several sheets or foils, whereby such an element is provided between consecutive sheets or foils of said package thereby facilitating the separation of said sheets or foils from each other and rendering directly Visible whether or not the latter are correctly superposed.

3. A package of thin transparent cellulose 15 sheets or foils arranged in superposed relationship and tending, under the influence of frictional contact, to adhere to each other, an adhesion-reducing element of electrically conductive material secured to at least a portion of each sheet on at least one side of said sheet and extending to and along the edge thereof, said elements being identical in configuration and being located at corresponding points on said several sheets or foils, whereby such an element is provided between consecutive sheets or foils of said package thereby facilitating the separation of said sheets or foils from each other and rendering directly visible whether or not the latter are correctly superposed, and means adjacent one edge. of said sheets or foils for binding them together into book form.

FRIEDRICH KRONER. 

